Explain what the system load average in Linux means and how it is calculated

The system load average in Linux shows the average number of processes that are either in the running state or waiting to run (for example, in the queue for the CPU) over a certain period of time. Usually, three values are displayed — for the last 1, 5, and 15 minutes.

The values are calculated as a moving average of the number of processes in the CPU queue and processes currently executing. For example, a load average of 1.0 on a system with a single core means the CPU is 100% loaded. If the value exceeds the number of cores, it indicates that the load is greater than what the CPU can handle without waiting.

For example: if you have a 4-core processor, a load average of 2.0 means half load, and 5.0 indicates overload, where processes are waiting in the queue.